Fluid conveying cannulas have a wide variety of applications during invasive surgical operations. For example, coronary operations such as heart bypass surgery utilizes a venous cannula for removing oxygen depleted blood from the vascular system and arterial cannulas for returning oxygenated blood to the vascular system. Both venous and arterial cannulae are usually inserted through incisions cut into the right or left atrium, the vena cava oratium and aorta, respectively. Typically, the incision in which the cannula is inserted is surrounded by purse-string sutures which, when drawn tight around the inserted cannula will effectively prevent fluid from escaping the vessel.
Tourniquets are commonly used to contain the free ends of the suture thread. Typically, the tourniquets are free lengths of tubing through which the free ends of the suture thread are pulled through after creation of the purse-string suture. Once the purse-string suture has been drawn sufficiently tight around the inserted cannula, the free end of the suture thread is held in a fixed position with respect to the tourniquet by one of several conventional means such as wrapping the suture thread around a button, frictionally retaining the free end of the suture thread by inserting a cone-shaped plug into the end of the tourniquet or, alternatively, clamping the tourniquet closed around the suture thread by use of a conventional surgical clamp. Once the free ends of the suture threads have been sufficiently contained, then the tourniquet tubes are typically manually tied to the cannula to hold the sutures, tourniquet and cannula in place.
A recent development in cardiovascular surgical procedures is to conduct minimally invasive surgery which utilizes smaller apertures formed in the chest wall rather than cutting the sternum and spreading open the entire rib cage, as usually done in conventional open heart surgery. While there are many benefits being realized by minimally invasive surgical procedures, these procedures place many challenges on the surgeon as a result of the far smaller access aperture available to the surgeon as he or she performs the surgery. In view of the relative size of the access aperture, simplification of any and all equipment utilized in the surgical procedure can simplify these challenging procedures. The cannula having integral suture tourniquet takes less space in the surgical filed than a conventional cannula and thus it is particularly adapted for minimally invasive surgery.